In the first stage of meiosis, prophase I, tetrads are formed.
Mitosis and cytokinesis. In eukaryotes the processes of DNA replication and cell division occur<span> at different times of the </span>cell division<span> cycle. During </span>cell division<span>, DNA condenses to form short, tightly coiled, rodlike chromosomes. Each chromosome then splits longitudinally, forming two identical chromatids.
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Like a wet sponge, soil already saturated from previous rainfall can't absorb much more ... thus more rainfall will become surface runoff.
The rocky upper layer of the solid earth is called the "lithosphere". This rocky part includes the brittle upper portion of the mantle and also of the crust. It is bounded by the atmosphere above and of the asthenosphere which is another part of the upper portion of the mantle.
